merge<T> method
Implementation
void merge<T>(ConstructType<T> obj, String knot) {
final idx = _idx[obj.name];
final knotIdx = _idx[knot];
if (idx == null) {
throw StateError('Missing type index for $obj.');
}
if (knotIdx == null) {
throw StateError('Missing type index for $knot.');
}
_types[idx] = _types[knotIdx];
// Delete the type.
_types.removeAt(knotIdx); // _types.splice(knotIdx, 1);
_idx.remove(knot);
}